New research in mice may be a first step toward a breast cancer vaccine for humans. The findings, published online Sunday and scheduled to run in the June 10 issue of the journal Nature Medicine, found that mice who were genetically engineered to be at high risk for breast cancer were effectively immunized against the disease after being injected with a breast cancer-specific antigen (or substance that prompts the immune system to churn out antibodies), while mice that were also susceptible to the disease but weren’t given the antigen did go on to develop breast cancer.

Dr. Vincent Tuohy, an immunologist at the Lerner Research Institute at the Cleveland Clinic and the lead investigator of the study, said in a statement:

“We believe that this vaccine will someday be used to prevent breast cancer in adult women in the same way that vaccines have prevented many childhood diseases… If it works in humans the way it works in mice, this will be monumental. We could eliminate breast cancer.”

The researchers focused their vaccination efforts on the α-lactalbumin protein, which is only found in healthy women while breast-feeding, but is also found in a majority of breast cancers. If the vaccine works in women as effectively as it did in mouse trials, Touhy and colleagues say that they should be able to spur the immune system to specifically target α-lactalbumin, halting the development of breast cancer for many women.

Of course, because it targets a protein present during lactation, if the vaccine works as intended it would mean that women giving the vaccine during their child-bearing years would not be able to breastfeed — surely a significant trade-off, but perhaps a welcome one for those at high risk for the disease who might consider other drastic measures for cancer prevention, such as prophylactic mastectomy.

While the step from animal studies to human trials is a large one, should all go to plan the researchers conclude that:

“… α-lactalbumin vaccination may provide safe and effective protection against the development of breast cancer for women in their post-child-bearing, premenopausal years, when lactation is readily avoidable and risk for developing breast cancer is high.”

In other words, should human trials confirm these initial findings, a breast cancer vaccine may be added to the growing arsenal of tools used to overcome cancer.